1. Field of the Invention
This invention relates to a spreading head for a wafer sheet coating machine, comprising a wafer sheet conveyor, which is optionally adapted to be lowered, a rotating spreading roller disposed above said conveyor, and sizing means, which are also disposed above said conveyor and adapted to cooperate with the spreading roller so as to control the thickness of the layer of spreadable composition which is being transferred by the spreading roller, said spreading roller and said sizing means defining a lower boundary of a reservoir, which is adapted to contain said spreadable composition and is laterally defined by platelike elements.
2. Description of the Prior Art
In a known spreading head for a wafer sheet coating machine, platelike elements are resiliently urged against the end faces of the spreading roller and are provided with upper and lower scraping bars which cooperate with the end faces of the roller and along the upper half of the roller, extend beyond the periphery of the roller and cause particles of the composition to be returned from the end face of the roller into the reservoir for the spreadable composition. A passage extending along the end face of the roller is defined by the upper and lower scraping bars and always provides a communication between the reservoir for the spreadable composition and the environment so that spreadable composition can escape through said passage during a prolonged standstill of the spreading roller.